I have wanted to brush up on my high-school calculus for a long time and kept trying several books, but was finding it difficult to grasp the basics as they are always presented in a confusing manner. But once I started reading this book published in 1945, I could not really keep it down, as it explained the very basics in a step-by-step method. I enjoyed and relished it like a novel for two weeks, with a very easy to read language usage for a book on calculus. I highly recommend this book if you find calculus a bit difficult to understand. I think, the best aspect of the book are the various illustrated solved examples within each chapter, which make the concepts really understandable. I did not need to do the end of the chapter exercises, but if you are in high school, then I would recommend you practice the questions as well. One of the best books I have read in a long time.